Requires specific chemicals; see Materials for more details.
For your convenience, a kit is available for purchase from our partner Home Science Tools.

Cost

Average ($50 - $100)

Safety

Adult supervision is required. This science project involves creating small, controlled fires. Make
sure you follow all the safety guidelines in the Procedure.

Abstract

Astronomers can figure out what distant stars are made of (in other words, their atomic composition) by measuring what type of light is emitted by the star. In this science project, you can do something similar by observing the color of flames when various chemicals are burned.

Objective

To investigate the colors produced when different chemicals are burned.

Share your story with Science Buddies!

Yes,I Did This Project!
Please log in (or create a free account) to let us know how things went.

APA Style

Introduction

All matter is made of atoms. Atoms have a nucleus, which consists of protons and neutrons,
and is surrounded by electrons. The nucleus is concentrated in a very small space, about 10-15 m.
An entire atom is on the order of 10-10 m, so the electrons are relatively far from the nucleus, and, strangely enough, atoms are mostly empty space.

Physicists have found that the electrons traveling around the atomic nucleus can have only certain amounts of energy, called energy levels. In other words, the energy levels of atomic electrons are quantized. If electrons gain energy, they can move from one energy level up to a higher level, but these different energy levels are not continuous—they come in discrete steps. (Watch the animation in Figure 1 to see an electron gain energy and move up to a higher energy level.) This fundamental discovery is known as quantum mechanics. Quantum mechanics describes how an atom's electrons interact with electrons of other atoms and with photons.

Figure 1. In this animation, the red circle represents an atom's nucleus and the blue circle is an electron orbiting around the atom. The black rings are different energy levels at which the electron can be. When the electron gains energy (represented by the red arrow going toward the electron), the electron moves to a higher energy level. When the electron loses energy (represented by the red arrow moving away from the electron), the electron moves to a lower energy level. (Animation credits: Kurzon)

Atomic electrons at higher energy levels can also lose energy, dropping down to a lower energy level. (You can also see this in the animation in Figure 1.) Again, the electron moves from one allowed energy state to another. The lost energy can be carried away in the form of heat (vibrational energy) or in the form of light—when the electron reverts to a lower energy state, a photon of light is produced. The photon produced will have an energy equal to the difference between the electron's initial high energy state and the later lower-energy state. For visible light, we perceive these differences in photon energy as differences in the color of the light. Because different types of atoms have different gaps between their energy levels, they make light of different colors when their electrons lose energy.

Not only can astronomers use this knowledge to figure out the atomic composition of distant stars, but it can also be used to create fireworks shows. Have you ever watched a fireworks show and wondered how all the different colors—amazing reds, yellows, oranges, blues, purples, greens, and more—are made? The color, or colors, that a firework makes depends on what chemicals are in the firework. These chemicals are various metal compounds that burn when the firework goes off, and burning the compounds is what makes the colors, like the ones shown in Figure 2.

Figure 2. The beautiful colors of fireworks, like the ones shown here, are the result of atomic electrons emitting energy as light. (Image credits: Semnoz)

In this science project, you will use a procedure that is similar to flame photometry or a flame test to observe the color of light produced when various metal compounds are burned. You will need an adult to help you with this experiment, and you will have to perform the experiment extremely carefully so that the flames stay small and under control. What colors will different chemical compounds produce?

Terms and Concepts

Atom

Proton

Neutron

Electron

Photon

Fireworks

Metal

Flame photometry

Flame test

Spectral lines

Questions

How are the colors produced by a chemical when it burns related to the atomic structure of the chemical?

What is flame spectrometry and how is it used by physicists and chemists?

How does this science project relate to what astronomers do when they are trying to identify the atomic makeup of a star?

In the chemicals used in this science project, which elements in the compounds are metals?

Bibliography

Here are some good references to get you started with your background research on spectral lines and flame tests:

News Feed on This Topic

,
,

Note: A computerized matching algorithm suggests the above articles. It's not as smart as you are, and it may occasionally give humorous, ridiculous, or even annoying results! Learn more about the News Feed

Experimental Procedure

Safety Note: This experiment requires adult supervision.
Do not breathe in dust from the chemicals, and wear gloves when handling them to prevent contact with skin. Also, avoid breathing combustion fumes produced during this experiment.

The results will be most clear in the dark. We suggest performing this science experiment outside in the evening on a nonflammable surface like brick, concrete, cement, or other driveway surface. Make sure that there are no flammable materials nearby. Be prepared for an emergency with a container of water. A fire extinguisher would also be a great alternative.

Preparing the Chemical Skewers

Follow the step-by-step instructions below and click through the
slideshow to see how to prepare the chemical skewers.

Slideshow with step-by-step instructions viewable online.

Click through the
slideshow to see how the chemical skewers are prepared.

Do your background research so that you are knowledgeable about the terms, concepts, and questions
in the Background section.

Have an adult present when you do the experiment, and follow all of the safety precautions mentioned at the beginning of the Procedure.

Several hours before sunset (a day or more is also fine), prepare the bamboo skewers.

Fold a piece of masking tape around the blunt end of each skewer to make labels (a total of 12 skewers) and write the name of a chemical on each skewer's label. You should label three skewers for each chemical.

Apply a thin layer of glue to the
last 2–3 centimeters (cm) of the tip of a skewer. You can squeeze the glue directly from the glue bottle onto the skewer.

While wearing the chemical goggles and disposable gloves, dip the glue-coated tip end of the skewer in the jar of chemical. Twist the skewer back and forth a bit to evenly coat the skewer with the chemical. Set it on a piece of scrap paper to dry. Important: Be sure to keep the scrap paper away from all children and pets as the skewers dry.

Make sure the name of the chemical on the skewer label is a match for the chemical you are using.

If you are not using the Science Buddies Kit, you may need to put your chemicals into vials or small baggies to do this step. The Science Buddies Kit chemical jars are just the right size to coat the skewer in.

Repeat steps 5 and 6 until you have made three skewers for each of the chemicals.

Let the skewers dry for at least 2 hours before performing the flame tests.

Conducting the Flame Tests

Follow the step-by-step instructions below and click through the
slideshow to see how to conduct the flame tests.

Slideshow with step-by-step instructions viewable online.

The flame test should be conducted outside, in the dark (or at twilight). Adult supervision is needed.

Find a hard, nonflammable surface outside for the flame test. A driveway, sidewalk, or brick/concrete/cement patio are all examples of a good testing surface.

Bring the dried chemical skewers (make sure they have dried for at least 2nbsp;hours first) and all other materials outside. You may find it easiest to use a flashlight or other outdoor light while you are getting set up. When you are done setting up and you are ready to test the skewers, make sure to turn off the light(s).

Place a solid fuel tablet on a square of aluminum foil on your nonflammable surface.

As a safety precaution, make sure to have a container of water with you. A fire extinguisher would be a great alternative. If you are using a video camera, start recording.

Have an adult use a match to light the solid fuel tablet. You may find that laying the lighted match on the foil next to the tablet is the easiest way to get the tablet to start burning. Note the color of the flame in your lab notebook. If you are using a digital camera to document your experiment, take a picture of the burning tablet.

Once the solid fuel tablet is burning, carefully take a skewer and hold the chemical-coated end in the flame.
Be sure not to breathe the fumes or smoke from the burning skewer.
Observe the flame color and record it in your lab notebook. Take a photo if you are using a digital camera for documentation.

Tip: You may be able to see the color in the tablet's flame, or by holding the skewer away from the flame (once the chemical has caught on fire) and looking at the flame on the chemical-coated end of the skewer.

The skewer may also catch fire after a few moments. Simply remove it from the flame and blow it out like a birthday candle. You can also extinguish the skewer in the container of water.

Repeat step 7 for all 12 skewers (3 per chemical). Record all your observations in your lab notebook.

When you are done, either wait for the solid fuel tablet to burn itself out, or extinguish it by carefully putting a heat-resistant bowl over the tablet.

When you are sure everything has been extinguished, you can dispose of the aluminum foil, used chemical-coated skewers, and spent fuel tablet in the garbage.

What colors were produced as each chemical burned?

Sodium chloride (table salt) and strontium chloride both have chloride, but have a different metal (sodium versus strontium). Are the flame colors produced by these two compounds similar or different? What does this tell you about the source of the color?

If you like this project, you might enjoy exploring these related careers:

Everything in the environment, whether naturally occurring or of human design, is composed of chemicals. Chemists search for and use new knowledge about chemicals to develop new processes or products.
Read more

Physicists have a big goal in mind—to understand the nature of the entire universe and everything in it! To reach that goal, they observe and measure natural events seen on Earth and in the universe, and then develop theories, using mathematics, to explain why those phenomena occur. Physicists take on the challenge of explaining events that happen on the grandest scale imaginable to those that happen at the level of the smallest atomic particles. Their theories are then applied to human-scale projects to bring people new technologies, like computers, lasers, and fusion energy.
Read more

Our universe is full of matter and energy, and how that matter and energy moves and interacts in space and time is the subject of physics. Physics teachers spend their days showing and explaining the marvels of physics, which underlies all the other science subjects, including biology, chemistry, Earth and space science. Their work serves to develop the next generation of scientists and engineers, including all healthcare professionals. They also help all students better understand their physical world and how it works in their everyday lives, as well as how to become better citizens by understanding the process of scientific research.
Read more

When you hear the word chemicals, you might think of laboratories and scientists in white coats; but actually, chemicals are all around you, as well as inside of you. Everything in the world is made up of chemicals, also known as matter, or stuff that takes up space. Chemistry is the study of matter—what it is made of, how it behaves, its structure and properties, and how it changes during chemical reactions. Chemistry teachers are the people who help students understand this physical world, from the reactions within our own bodies to how soaps and detergents work and why egg proteins can keep a cookie from crumbling. They prepare the next generation of scientists and engineers, including all healthcare professionals. They also help also students develop scientific literacy.
Read more

Variations

You could try this science project using other metal compounds known to produce certain flame colors when burned. Check out the resources in the Bibliography section for some ideas on how to do this. Be sure to always look into and follow all proper safety precautions when handling and burning different chemicals. What colors do other metal compounds make when burned?

Share your story with Science Buddies!

Yes,I Did This Project!
Please log in (or create a free account) to let us know how things went.

Ask an Expert

The Ask an Expert Forum is intended to be a place where students can go to find answers to science questions that they have been unable to find using other resources. If you have specific questions about your science fair project or science fair, our team of volunteer scientists can help. Our Experts won't do the work for you, but they will make suggestions, offer guidance, and help you troubleshoot.

Contact Us

If you have purchased a kit for this project from Science Buddies, we are pleased to answer your questions.

In your email, please follow these instructions:

What is your Science Buddies kit order number?

Please describe how you need help as thoroughly as possible:

Examples

Good QuestionI'm trying to do Experimental Procedure step #5, "Scrape the insulation from the wire. . ." How do I know when I've scraped enough?Good QuestionI'm at Experimental Procedure step #7, "Move the magnet back and forth . . ." and the LED is not lighting up.Bad QuestionI don't understand the instructions. Help!Good QuestionI am purchasing my materials. Can I substitute a 1N34 diode for the 1N25 diode called for in the material list?Bad QuestionCan I use a different part?

Related Links

News Feed on This Topic

,
,

Note: A computerized matching algorithm suggests the above articles. It's not as smart as you are, and it may occasionally give humorous, ridiculous, or even annoying results! Learn more about the News Feed

Looking for more science fun?

Try one of our science activities for quick, anytime science explorations. The perfect thing to liven up a rainy day, school vacation, or moment of boredom.

Compared to a typical science class, please tell us how much you learned doing this project.

Much more
More
About the same
Less
Much less

What was the most important thing you learned?

characters left

Science Buddies materials are free for everyone to use, thanks to the support of our sponsors. What would you tell our sponsors about how Science Buddies helped you with your project?

characters left

Optional:Attach a picture of your project (JPG, JPEG, GIF, PNG only)

Optional:Caption for picture

characters left

You can find this page online at: https://www.sciencebuddies.org/science-fair-projects/project-ideas/Phys_p058/physics/rainbow-fire

You may print and distribute up to 200 copies of this document annually, at no charge, for personal and classroom educational use. When printing this document, you may NOT modify it in any way. For any other use, please contact Science Buddies.